Problem in downstream library if built with a gcc major version different from the one used to build manifpy

[traversaro]

In ami-iit/bipedal-locomotion-framework#514 a downstream library (blf) had runtime failures due to being compiled by a gcc major version different. We should handle this somehow, even if at the C++ level as far as I know gcc 9 and 10 should produce ABI compatible code.

[traversaro]

Related issue: ami-iit/bipedal-locomotion-framework#386 .

[traversaro]

Yesterday night I checked a bit pybind11 code, and it seems the issue here is not related to ABI layout of pybind11 objects, but rather the stability of the type information used in pybind11 (see https://github.com/pybind/pybind11/blob/522c59ceb27e83750c121d5da3d8b67ac446b754/include/pybind11/pybind11.h#L1026 and the related code). At the beginning I tought it was related to the info returned by std::typeid operator, but actually I could not find any use of such operator in pybind11.